Index: gcc/regrename.c
===================================================================
--- gcc/regrename.c	(revision 224532)
+++ gcc/regrename.c	(working copy)
@@ -942,19 +942,22 @@ regrename_do_replace (struct du_head *he
       int reg_ptr = REG_POINTER (*chain->loc);
 
       if (DEBUG_INSN_P (chain->insn) && REGNO (*chain->loc) != base_regno)
-	INSN_VAR_LOCATION_LOC (chain->insn) = gen_rtx_UNKNOWN_VAR_LOC ();
+	validate_change (chain->insn, &(INSN_VAR_LOCATION_LOC (chain->insn)),
+			 gen_rtx_UNKNOWN_VAR_LOC (), true);
       else
 	{
-	  *chain->loc = gen_raw_REG (GET_MODE (*chain->loc), reg);
+	  validate_change (chain->insn, chain->loc, 
+			   gen_raw_REG (GET_MODE (*chain->loc), reg), true);
 	  if (regno >= FIRST_PSEUDO_REGISTER)
 	    ORIGINAL_REGNO (*chain->loc) = regno;
 	  REG_ATTRS (*chain->loc) = attr;
 	  REG_POINTER (*chain->loc) = reg_ptr;
 	}
-
-      df_insn_rescan (chain->insn);
     }
 
+  if (!apply_change_group ())
+    return;
+
   mode = GET_MODE (*head->first->loc);
   head->regno = reg;
   head->nregs = hard_regno_nregs[reg][mode];